The present invention relates broadly to devices for handling articles and, more particularly, to an apparatus that is removeably mountable onto a pallet jack for use therewith in lifting, tilting, transporting, and relocating articles, such as stacks of trays, boxes, furniture or the like from one location to another. A motorized truck having the maneuverability of a pallet jack and upon which the apparatus is permanently mounted is also contemplated within the scope of the present invention.
Many different types of material handling devices or trucks are known in the art. Such devices range from a simple hand truck to a more complex fork lift device. A hand truck requires the manual strength of the operator to assist in lifting, tilting, and maneuvering the load, which is supported on the hand truck on a relatively short platen base. Generally, a hand truck and operator are only capable of maneuvering a load of up to several hundred pounds. In contrast, a fork lift device is generally motorized, has a place for the operator to stand or sit, and is capable of lifting and transporting extremely heavy loads weighing up to several thousand pounds or more. In addition, a standard fork lift usually has fairly long and thick forks for lifting, supporting, and maneuvering heavy or bulky loads, such as palletized loads, industrial machines or equipment.
Specialized material handling trucks having capabilities falling somewhere between hand trucks and fork lifts are also known in the art. One example of such a device is shown in Avitan et al., U.S. Pat. No. 5,478,196, which discloses a small truck that is designed for loading, tilting, and transporting two stacks of interlocking bread trays in side-by-side fashion. Although most of the bread industry still uses hand trucks to load and unload stacks of bread trays from a truck trailer, the device in Avitan offers some benefits.
The device disclosed in Avitan, however, has numerous disadvantages, which, as will be seen, are overcome by the apparatus of the present invention. For example, in order to move stacks of bread as disclosed in Avitan, a bread manufacturer only has the option of purchasing the entire apparatus or truck described in the Avitan patent. Since most bread manufacturers own pallet jacks, there is a need to provide a material handling apparatus that can be mounted onto a pallet jack, which obviates the need for purchasing an entirely new transport vehicle upon which an apparatus is permanently mounted. In addition, the truck disclosed in Avitan has the operator facing away from the stacks of bread trays being loaded onto the truckxe2x80x94while this allows the operator to see clearly when driving the loaded truck in a forward direction, it is quite difficult for the operator to see while backing the truck into correct loading and unloading position. Further, the Avitan patent discloses a standard platen (solid or divided) for disposition beneath the stacks of bread trays to be moved. To fit beneath stacks of bread trays, the standard platen must be fairly thin, which tends to bend easily especially after repeated use. Another disadvantage of the Avitan design is having the pivot point of the tiltable upright approximately halfway up the height of the upright. The high pivot point creates at least two problems: first, since the lower half of the tilted stacks must tilt away from the truck, the operator must ensure that there is sufficient space on the other side of the stacks before the load is tilted; second, the high pivot point places the center of gravity of the load further toward the rear of the truck which decreases the stability of the loaded truck during transport. In addition, the Avitan device does not disclose a means or method for maintaining the stacks of bread trays in abutment with or adjacent to the tiltable upright during tilting or transport. In practice, when being tilted, the stacks of trays may actually lean away from the upright. Such leaning not only increases the lateral instability of the load being carried, but also increases the amount of force exerted on the platen during the tilting process, which, in turn, increases the likelihood that the platen will bend. Further, the truck disclosed in Avitan can only carry as many bread trays as will fit, while tilted, through the height of the opening of a truck trailer into which the stacks of bread trays are being loaded or unloaded. Further, the truck in the Avitan patent is limited to the handling of stacks of bread trays. There is no disclosure or suggestion to use the truck to transport other types of articles, such as furniture, boxes, or similar uniformly-shaped articles. Finally, there is no disclosure or suggestion that the truck have the capability of raising and lowering the articles being moved along the height of the upright to allow the articles to be loaded onto or unloaded from a raised platform or stack, nor is there any disclosure or suggestion that the platen or base have the capability of being adjusted in a side to side fashion to allow the base to be properly centered before loading the article or to allow the article to be side shifted relative to the upright after it has been loaded.
It is therefore an object of present invention to provide an apparatus having a base and a back support member that can be selectively mounted and demounted to and from a pallet jack for use therewith in moving articles from one location to another.
It is a further object of the present invention to provide such a mountable apparatus with a pivot location generally at the bottom of the back support member.
It is also an object of the present invention to provide such a mountable apparatus with a first clamp member disposed along the upper half of the back support member for maintaining the articles in abutment with or adjacent the back support member during tilting and/or movement of the articles from one location to another.
It is another object of the present invention to provide such a mountable apparatus for use in moving stacks of objects that is capable of displacing at least one of the objects off of the stack whereby the vertical height of the tilted stack is reduced, which allows a stack of objects exceeding the vertical height restrictions of the opening of a truck trailer to be successfully loaded onto the truck trailer.
It is a further object of the present invention to provide such a mountable apparatus wherein the base may be raised and lowered along the height of the back support member to allow the articles being moved to be raised and lowered for loading onto or unloading from a raised platform.
It is a further object of the present invention to provide such a mountable apparatus wherein the base may be adjusted in side to side fashion relative to the back support member whereby the base may be properly centered below a load prior to loading and/or whereby the load may be properly adjusted across to the back support member after being loaded.
It is also an object of the present invention to provide such a mountable apparatus with a base comprising a plurality of laminated forks, each of such forks being selectively mountable and demountable onto the back support member and being tapered at one end for sliding under the articles to be moved.
Alternatively, it is an object of the present invention to provide such a mountable apparatus with a base comprising a laminated platen, mountable and demountable onto the back support member and being tapered at one end for sliding under the articles to be moved.
It is a further object of the present invention to provide such a mountable apparatus having each of and/or varying combinations of the above-mentioned novel features.
It is a further object of the present invention to provide a transport vehicle having each of and/or varying combinations of the above-mentioned novel features.
To that end, the present invention provides an apparatus for moving an article from one location to another, comprising a housing adapted for selective mounting to and demounting from a pallet jack, and an article engaging and lifting member attached to the housing and comprising a base for disposition beneath the article to be moved for bottom support thereof and a back support member extending from the base at a generally perpendicular orientation for side support of the article. The article engaging and lifting member is pivotally attached to the housing adjacent the bottom of the back support member to define a first pivot location. The apparatus further comprises means associated with the article engaging member and with the housing for tilting the article engaging and lifting member about the first pivot location. The tilting means comprises a force application member that either extends between and is connected to the housing and the back support member at a spacing from the first pivot location or connects to the housing and the article engaging and lifting member generally at the first pivot location whereby a force applied to the back support member by the force application member results in tilting movement of the article engaging and lifting member about the first pivot location.
In one embodiment of the present invention, the apparatus further comprises a first clamp member disposed on the back support member at a spacing from the first pivot location for engaging the article to be moved and maintaining the article adjacent the back support member. The first clamp member comprises at least one hook member pivotally mounted to the back support member for pivotal movement into and out of clamping engagement with the article to be moved. In addition, the first clamp member may be vertically adjusted along the back support member to accommodate different types or sizes of articles or objects being moved.
In another embodiment of the present invention, when the article being moved is a stack of objects, the apparatus further comprises an upper displacement member mounted to the back support member which engages an upper object of the stack and displaces the upper object off of the stack over the back support member whereby the vertical height of the tilted stack is reduced. The upper displacement member comprises a rack mounted at a top of the back support member and having a length extending generally perpendicular to the back support member in a direction opposite that of the base; and an upper engagement member moveably mounted on the rack for engaging, lifting, and moving the upper object along the length of the rack. The upper engagement member comprises a beam member movably mounted along the length of the rack, an engagement plate defining a plurality of openings therein and moveably mounted to the beam member for vertical and horizontal movement relative to the upper object, a second clamp member mounted to the beam member and adapted to project through one of the plurality of openings of the engagement plate and to engage and stabilize the upper object relative to the engagement plate, and a plurality of lifting fingers mounted to the engagement plate and projecting through others of the openings in the engagement plate, the lifting fingers engaging a side of the upper object during vertical movement of the engagement plate for lifting the upper object from the stack and pulling the upper object along the length of the rack in response to movement of the beam member.
In another embodiment of the present invention, the base is linearly moveable along the back support member for raising and lowering of the article relative to the back support member. In addition, the base may also be adjustable in side to side or horizontal fashion relative to the back support member.
In one embodiment, the base comprises a plurality of forks projecting outwardly in side by side, spaced relation from the back support member for disposition beneath the article for support thereof Preferably, the forks are laminated for increased strength and the thickness of each fork tapers on the end furthestmost from the back support member to more easily slide beneath an article being loaded. Alternatively, the base comprises a platen projecting outwardly from the back support member for disposition beneath the article for support thereof. Preferably, the platen is laminated for increased strength and the thickness of the platen tapers on the end furthestmost from the back support member to more easily slide beneath an article being loaded.
It is contemplated within the scope of the present invention that any of the above features may be used singly or in combination with each other. Further, it is contemplated within the scope of the present invention, that any one or combination of the above features could be permanently or fixedly mounted on a transport vehicle, which would provide the same functionality as an apparatus selectively mounted to and demountable from the pallet jack.
By the above, the present invention provides either an apparatus that is adapted for selective mounting to and demounting from a pallet jack for use therewith or a transport vehicle having an apparatus described herein permanently mounted thereto, either of which can effectively and efficiently transport articles or stacks of objects, such as boxes, furniture, trays, or the like from one location to another.